To use, invoke `cmake` with argument `--preset dev-mode`.
Solves one item in #1235.
One disadvantage over `./configure --enable-dev-mode` is that CMake
does not provide a way to "hide" presets from users. That is,
`cmake --list-presets` will list dev-mode, and it will also appear
in `cmake-gui`, even though it's not selectable there due to bug
https://gitlab.kitware.com/cmake/cmake/-/issues/23341. (So in our
case, that's probably rather a feature than a bug.)
We curently use version 3 presets which require CMake 3.21+.
Unfortunately, CMake versions before 3.19 may ignore the `--preset`
argument silently. So if the preset is not picked up, make sure you
have a recent enough CMake version.
More unfortunately, we can't even spell this warning out in
CMakePresets.json because CMake does not support officially support
comments in JSON, see
- https://gitlab.kitware.com/cmake/cmake/-/issues/21858
- https://gitlab.kitware.com/cmake/cmake/-/merge_requests/5853 .
We could use a hack hinted at in
https://gitlab.kitware.com/cmake/cmake/-/issues/21858#note_908543
but that's risky, because it could simply break for future versions,
and we probably want to use presets not only for dev mode.
